The use of flexography to print sheets of cardboard intended, for example, to form boxes, is currently known. This technique consists of passing cardboard sheets or laminar elements on a horizontal plane between rollers installed in a digital printing station.
To do this, the use of an insertion device to feed laminar bodies (of different sizes) into a graphic printing station like the one described above is known, and is described in the Spanish patent no ES 2 547 473 granted to this applicant.
Traditionally, pairs of cylinders have been used as the pulling elements after the insertion device to finish inserting the cardboard sheet into the line for printing, die-cutting, folding, etc. The pulling of the cardboard sheets such that they pass through a defined space between two cylinders results in the lamination of the sheets to a certain degree, which, in the specific case of corrugated cardboard sheets, may generate an undesired effect of loss of mechanical properties in regard to strength.
In addition, the applicant has no knowledge of any invention at the present time that is equipped with all of the features covered in this description.